title: Recurrent primary pleomorphic adenomas of salivary gland origin: intrasurgical rupture, histopathologic features, and pseudopodia.
abstract: BACKGROUND
  The rate of tumor recurrence after surgery for benign salivary gland pleomorphic adenoma varies considerably in different clinical settings and seems to depend to a great extent on the surgical technique used. The importance of tumor spillage for subsequent recurrence has recently been questioned. The current follow-up study was undertaken to ascertain whether intrasurgical rupture, tumor spillage, or any histopathologic feature might have had an impact on the rate of recurrence.
  
  
  METHODS
  The medical records of all 255 patients operated on for benign salivary gland pleomorphic adenoma between the years 1974 and 1993 at the Department of Otorhinolaryngology, Huddinge University Hospital, were reviewed. All patients alive in April 1995 (n = 230) were sent a simple questionnaire. Two hundred thirteen of these patients received follow-up. All cases of tumor recurrence after surgery or intrasurgical rupture of the tumor capsule were reviewed histopathologically.
  
  
  RESULTS
  Two (7.1%) of the 28 patients who had macroscopic capsule rupture during surgery experienced recurrence at a later stage. This was not a statistically higher rate than the 4.1% recurrence rate for the rest of the material. As many as 5 of the 9 primary tumors that subsequently recurred (56%) sent fingerlike tumor extensions or pseudopodia outside the pseudocapsule. The rate of occurrence of such structures was statistically higher than that of the tumors that ruptured during surgery (25%) and the examined uncomplicated cases (8%).
  
  
  CONCLUSIONS
  Occurrence of pseudopodia--microscopic fingerlike formations of tumor tissue that extend beyond the main lump of the tumor--is a significant risk factor for local recurrence.
authors.affiliation: Department of Otorhinolaryngology, Huddinge University Hospital, Sweden.
authors.forename: G
authors.initials: G
authors.lastname: Henriksson
authors.forename: K M
authors.initials: KM
authors.lastname: Westrin
authors.forename: B
authors.initials: B
authors.lastname: Carlsöö
authors.forename: C
authors.initials: C
authors.lastname: Silfverswärd
mesh_terms: D008949:Adenoma, Pleomorphic / Q000209:etiology* / Q000473:pathology / Q000601:surgery; D005500:Follow-Up Studies; D006801:Humans; D007431:Intraoperative Complications; D009364:Neoplasm Recurrence, Local / Q000209:etiology*; D009366:Neoplasm Seeding; D011554:Pseudopodia; D012468:Salivary Gland Neoplasms / Q000209:etiology* / Q000473:pathology / Q000601:surgery; D013514:Surgical Procedures, Operative / Q000009:adverse effects*; D016896:Treatment Outcome